The Museo Nacional de Bellas Artes (MNBA) ("National Museum of Fine Arts" in English) is an Argentine art museum in Buenos Aires, located in the Recoleta section of the city. The MNBA inaugurated a branch in Neuquén in 2004.

Argentine painter and art critic Eduardo Schiaffino was the first director of the MNBA, which opened on 25 December 1895 in a building on Florida Street which today houses the Galerías Pacífico shopping mall. In 1909 the museum moved to a building in Plaza San Martín, originally erected in Paris as the Argentine Pavilion for the 1889 Paris exhibition, and later dismantled and brought to Buenos Aires. In its new home the museum became part of the International Centenary Exhibition held in Buenos Aires in 1910. Following the demolition of the Pavilion in 1932 as part of the remodelling of Plaza San Martín, the museum was transferred to its present location in 1933, a building originally constructed in 1870 as a drainage pumping station and adapted to its current use by architect Alejandro Bustillo.

The museum was modernized both physically and in its collections during the 1955–64 tenure of director Jorge Romero Brest. A temporary exhibits pavilion was opened in 1961, and the museum acquired a large volume of modern art though its collaboration with the Torcuato di Tella Institute, a leading promoter of local, avant-garde artists, and elsewhere; a Contemporary Argentine Art pavilion was later opened in 1980. This 1,536 square metres (16,533 sq ft) hall is the largest of 34 currently in use at the museum, which totals 4,610 square metres (49,622 sq ft) of exhibit space. Its permanent collection totals 688 major works and over 12,000 sketches, fragments, potteries and other minor works. The institution also maintains a specialized library, totalling 150,000 volumes, as well as a public auditorium. The MNBA commissioned architect Mario Roberto Álvarez to design a branch in the patagonian region city of Neuquén. Inaugurated in 2004, this museum holds 4 exhibit halls totaling 2,500 square metres (26,910 sq ft) and a permanent collection of 215 works, as well as temporary exhibits and a public auditorium.

The ground floor of the museum holds 24 exhibit halls housing a fine international collection of paintings from the Middle Ages up to the 20th century, together with the museum's art history library. The first floor's 8 exhibit halls contain a collection of paintings by some of the most important 20th-century Argentine painters, including Antonio Berni, Ernesto de la Cárcova, Benito Quinquela Martín, Eduardo Sívori, Alfredo Guttero, Raquel Forner, Xul Solar and Lino Enea Spilimbergo. The second floor's two halls, completed in 1984, hold an exhibition of photographs and two sculpture terraces, as well as most of the institution's administrative and technical departments.